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CHAPTER 10
Arnold-Chiari abnormality of the brain stem and cerebellum. Moreover, there are
congenital defects of the arch of the atlas either unilaterally or bilaterally. Furthermore,
there may be congenitally complete or partial absence of the odontoid process or separate
odontoid process (os odontoideum); the four groups of clinical symptomatology of the
latter has been described by Rowland
et al.
(1958). Klippel-Feil syndrome consisting
of hemivertebrae, and fusion of adjacent vertebrae and scoliosis of the cervical spine are
other examples of congenital anomalies in that region.
In the lumbo-sacral region, the most common anomalies are spina bifida, bilateral
or unilateral sacralization of the 5th lumbar vertebra and spondylolisthesis. Although the
latter cannot be regarded as a congenital anomaly as such, it develops as a result of a
structural vertebral defect, usually of the 5th lumbar vertebra, where the interruption
of the neural arch on either side at the pars inter-articularis represents the underlying
defect. Scoliosis due to vertebral abnormalities and neuropathies may also be mentioned
amongst the congenital anomalies.
Of the acquired anomalies of the vertebral column which may influence the character
of a fracture, mention has already been made of the ankylosing spondylitis. Certain
forms of chronic spondylosis of the elderly, as well as scoliosis after poliomyelitis or
muscular dystrophy, and the so-called idiopathic scoliosis may affect the type and
severity of spinal injuries. Fig. 41 shows a fracture-dislocation of T4 vertebra following a
car accident, resulting in profound lateral-upward displacement of the vertebral column
below the fracture in a case of idiopathic scoliosis causing an almost complete paraplegia
below T4. The patient, aged 20, sustained a bilateral haemothorax and a spastic paraplegia
below T5 but only incomplete sensory loss below Ty with some appreciation to pain
in Si on the right side. He also had sensation of fullness of the bladder and in due course
regained some bladder and sexual control in spite of most unusual lateral dislocation of
the broken spine.
(2) AETIOLOGICAL FACTORS
Careful history taking and analysis of the accident are essential in clarifying the mechan–
ism. In 1970,1 saw a young boy of 7, in the Bihar district of India, who, in a most unique
accident, sustained a complete tetraplegia below Cy, having been attacked by one of his
father's pet lions. X-rays did not show any fracture or dislocation of the cervical spine,
nor were there any signs of an external wound on the neck as a result of a bite or claws.
The aetiology and mechanism of the injury seemed to be obscure until I found a scar
over the boy's forehead. On further questioning the person who saw the accident and
came to the boy's rescue, it became clear that the boy had been thrown forward to the
ground by the heavy weight of the lion, hitting the ground with his forehead. It was,
therefore, obvious that in this case the mechanism of the cervical cord injury was that of a
temporary vertebral dislocation, resulting from a violent backward and upward move–
ment of the head and neck, which, however, reduced itself (commonly but wrongly called
whiplash mechanism). It is well known that in spinal cord injuries in children, X-rays
either do not reveal any bony injury or, if so, these are rarely significant (Guttmann, 1960;
Meinecke, 1969). Burke (1971) confirmed this fact on a larger material and explained the
